1. Technical Field
This disclosure is directed to wireless telecommunications systems, and more particularly, to user devices capable of communicating with multiple networks.
2. Description of the Related Art
In recent years, wireless devices such as smart phones and tablet computers have become increasingly sophisticated. In addition to supporting telephone calls, many mobile devices now provide access to the internet, email, text messaging, and navigation using the global positioning system (GPS). Furthermore, many mobile devices are capable of operating sophisticated applications, many of which may utilize the functionality mentioned above.
In large part due to their increased functionality, many wireless devices are capable of communicating with multiple networks using a single transceiver. For example, a transceiver of a wireless device may have a communications channel established with a first network (e.g., LTE, or Long Term Evolution, sometimes referred to as 4G), but may from time to time tune away to monitor for communications on a second network (e.g., a CDMA, or code division multiple access network). During the time the transceiver is tuned to the second network, it is unable to receive communications from the first network. When tuned to the second network, the transceiver may lose synchronization with the first network due to missing receiving important signaling messages. This loss of synchronization can prolong the amount of time in which communication and data transfer between the wireless device and the first network, as the re-establishment of synchronization upon tuning back to the first network may consume time. In some cases, the first network may drop the link with the wireless device altogether without the latter being informed.